Ayumi lives with her daughter and son-in-law. With her daughter constantly busy at work, Ayumi's marital life has been nonexistent for some time. Meanwhile, the son-in-law grows frustrated from being neglected by his wife and often vents to Ayumi. One evening, while sharing drinks and confiding in her, he catches a glimpse of Ayumi's alluring cleavage and impulsively takes her by force. Afterward, an awkward silence fills the air when they're alone. Yet sensing this might be their only chance, Ayumi and her son-in-law begin a secret affair, careful not to alert their daughter. Seizing stolen moments in the cracks of daily life, their hidden trysts grow increasingly intense, deepening the bond between them.